The present invention relates to the field of underwater marker buoy release systems, and more particularly to an electromagnetic marker buoy release.
There are many applications that require objects to be implanted upon the ocean floor, as for example, lobster traps, or underwater sensors. To facilitate eventual recovery of these objects, buoys are often used to mark the positions of such objects. However, buoys draw attention to the objects and make them vulnerable to being purloined or tampered with. To minimize these problems, the objects may include mechanisms for releasing a buoy after a predetermined period of time, or after the performance of some function.
Different types of buoy releases have been employed for this purpose, as for example, mechanical, explosive link, or corrodible link systems. However, each of these types have drawbacks.
The mechanical systems generally consist of some type of sliding or levered actuator which performs the release function. These systems tend to be relatively costly because they have many parts, some of which require precision tolerances. Another disadvantage of this type of system results from exposure to sea water which can eventually cause binding of the release mechanism due to organic growth or corrosion of the mechanism.
The explosive link systems utilize an explosive bolt or charge to break the connection between the float and the submerged object. For safety reasons, these types of devices require careful handling by specially trained personnel. Furthermore, systems incorporating explosive links can present a safety hazard if they inadvertently fire.
The simple corrosive link release system relies on sea water to corrode the connecting link until the marker is released. This type of release is dependent upon several factors including water temperature, water salinity, and water current flow across the link. Although these environmental factors may be accommodated by designing a corrodable link so that it may release within a predetermined period of time after deployment, these links cannot be used to signal completion of a process or a system failure.